Propulsion drive

ABSTRACT

The invention concerns a propulsion drive (P) with an underwater housing ( 6; 11 ) arranged on the bottom of a ship&#39;s hull, in which at least one propeller ( 5; 18 ) is mounted, being driven by a drive train of drive motor mechanisms ( 12 ) lying at least partly inside the underwater housing ( 6; 11 ), wherein a planet gear ( 4; 14, 15 ) is connected in series in the interior of the underwater housing ( 6; 11 ) to the at least one propeller ( 5; 18 ) and the planet gear ( 4; 14, 15 ) contains a sun wheel, which is configured as a part of a propeller shaft ( 2, 17 ), which is mounted in the underwater housing ( 6; 11 ) and on which the at least one propeller ( 5; 18 ) is seated outside of the underwater housing ( 6; 11 ).

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. §119 to German Utility Model Application No. DE 20 2007 004 477.1 filed Mar. 23, 2007, the entire contents of which are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention concerns a propulsion drive.

BACKGROUND OF THE INVENTION

Traditional propulsion drives known from practice contain, in an underwater housing, an underwater transmission with a bevel gear stage, which at the takeoff end provides the torque and the rotary speed for a propeller. This arrangement necessarily yields a diameter for the corresponding ring gear and also the underwater housing that is as much as 40% of the propeller diameter.

SUMMARY OF THE INVENTION

The present invention has and achieves the objective of creating a propulsion drive with an underwater housing whose diameter is smaller than in propulsion drives thus far known in practice.

For this, the invention creates a propulsion drive with an underwater housing, arranged on the bottom of a ship's hull, in which at least one propeller is mounted, being driven by a drive train of drive motor mechanisms, lying at least partly inside the underwater housing, while a planet gear is connected in series in the interior of the underwater housing to the at least one propeller and wherein the planet gear contains a sun wheel, which is configured as a part, more particularly, an integral component, of a propeller shaft, which is mounted in the underwater housing and on which the at least one propeller sits outside of the underwater housing.

One advantageous modification thereof consists in arranging another gear assembly between the planet gear and the drive motor mechanisms, while the other gear assembly is preferably a ring gear/bevel gear transmission, which contains in particular a bevel gearset.

Moreover, it can preferably be provided that a hydrodynamic coupling or a hydrodynamic converter is arranged between the planet gear and the other gear assembly, especially the bevel gear stage.

Moreover, it can advantageously be provided that the planet gear assembly contains three to six planet wheels.

Another preferred modification consists in providing two propellers, one of which is arranged and designed as a pusher propeller and one as the tractor propeller of the propulsion drive.

The propulsion drive of the invention can also be configured such that the drive motor mechanisms contain a motor arranged in the underwater housing, which is connected in series to the planet gear, and the motor is also preferably an electric motor, such as a permasyn, induction, synchronous, HTS or HY electric motor.

Furthermore, it can be preferably provided that the bearing of the sun wheel with propeller shaft in the underwater housing also absorbs the forces and torques of the propeller and directs them into the housing.

Another preferred embodiment consists in dividing the sun wheel and transmitting the forces and torques of the propeller and the planet gear via the connection, especially a screw connection.

Additional preferred embodiments are configured so that the sun wheel with propeller shaft is in a floating bearing or a double-sided bearing.

Furthermore, an alternative preferred embodiment is that a propeller is present, which is arranged and designed as a tractor propeller of the propulsion drive, and the propeller wash passes across the underwater housing. Yet another preferable alternative can be that a propeller is present, which is arranged and designed as a pusher propeller of the propulsion drive and which sucks across the underwater housing.

Thus, the invention lies in the field of underwater transmissions of a steerable propulsion drive, and especially for the rudder propeller, although the invention is also basically applicable to the azimuth drive.

Other preferred and/or advantageous configurations of the invention follow from the claims and combinations thereof, as well as all of the present documents of the application.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained more closely, merely as an example, making reference to the drawing, where

FIG. 1, in a schematic longitudinal section, shows a first embodiment of a propulsion drive, and

FIG. 2, in a schematic longitudinal section, shows a second embodiment of a propulsion drive.

DETAILED DESCRIPTION OF THE INVENTION

With the help of the following described embodiments and applications, represented in the drawings, the invention will only be explained as an example, i.e., it is not limited to these embodiments and applications or to the combinations of features within these embodiments and applications. Method and device features will also follow analogously from device and method descriptions.

Individual features which are indicated and/or represented in connection with a specific embodiment are not confined to this embodiment or the combination with the other features of this embodiment, but instead can be combined so far as is technically possible with any other variants, even if not discussed separately in the present documents.

Identical reference numbers in the individual figures and drawings designate identical or similar components, or those with the same or similar functions. The representations in the drawing will also point out such features as are not provided with reference numbers, regardless of whether such features are described subsequently or not. On the other hand, features which are contained in the present specification but are not visible or represented in the drawing are also immediately understandable by those in the art.

FIG. 1 shows schematically in a longitudinal section a first embodiment of a propulsion drive P. This propulsion drive P contains a bevel gear set 1, a sun wheel/propeller shaft 2, planet wheels 3 (only one of which is visible in FIG. 1), a planet gear 4, a propeller 5, an underwater housing 6 and a propeller shaft bearing 7.

Thanks to the arrangement of a planet gear 4, which is connected in series to the bevel gear set 1, the propeller torque is provided immediately in front of the propeller 5. This enables a small bevel gear set 1 as in traditional designs without such a planet gear 4. Thanks to the planet design with the load distributed over 3-6 planets, a smaller housing diameter can be realized, as in particular, around 30% of the propeller diameter. Thanks to the small housing diameter, which in practice means a smaller diameter for the pear shape of the underwater housing 6, the propeller wash surface is less blocked, which results in better propeller efficiency. This applies to the configuration as a pusher propeller, where the underwater housing 6 is arranged in front of the propeller 5, and also for a tractor propeller, where the propeller 5 sits in front of the underwater housing.

The special feature of this design is that the sun wheel is part of the propeller shaft 2 and thus is also mounted in the underwater housing 6.

Thanks to this design, it is possible to increase the speed reduction in the “underwater transmission,” which for the bevel gear set 1 is around 4. Speed reductions up to at 10 are possible. Thus, e.g., for an L-version (drive concept with vertically mounted electric motor), one can use an electric motor with higher speed (1200-1800 rpm). The electric motor with higher speed has smaller dimensions and so allows for a favorable design.

FIG. 2 shows schematically in longitudinal section a second embodiment of a propulsion drive P. This propulsion drive P contains an underwater housing 11, an electric motor 12, which stands for the drive motor mechanisms in general, a geared coupling 13, a sun gear 14 and planet wheels 15, of which only one can be seen, an internal gear 16, a sun wheel/propeller shaft 17, a propeller 18 and a propeller shaft bearing 19.

The configuration of the arrangement of the planet gear 4, with the sun wheel as part of the propeller shaft, as explained in connection with FIG. 1, can also be connected downstream of the electric motor 12 in the underwater housing 11, which could also be called an underwater pod. With this arrangement, one can use an electric motor 12 of higher speed (4-5 times the propeller speed), requiring much less space. Thanks to this feature, moreover, the forces and torques from the propeller, as well as the speed reduction to the propeller speed, are entirely disconnected from the electric motor 12.

As the drive motor, one can use a wide variety of electric motors, such as permasyn, induction, synchronous motors, etc., and also HTS and HY motors.

As already applies to the embodiment of FIG. 1, the special feature lies in the design of the “propeller shaft,” which integrates the sun wheel and is mounted in the underwater housing. All forces and torques from the propeller 18 and drive unit (drive motor/electric motor 12 or bevel gear transmission/bevel gear set 1), as well as the propeller thrust, are transferred via the bearing of the propeller shaft 2 and 17 with integrated sun wheel to the underwater housing 6 and 11.

The propulsion drive can be designed with a fixed propeller, and also with an adjustable propeller. The drive can be designed as a tractor propeller (the propeller is arranged in front of the underwater housing in the direction of travel) and/or as a pusher propeller (the propeller is arranged behind the underwater housing in the direction of travel).

The invention has been presented merely as an example by means of the embodiments in the specification and in the drawing and is not limited to these, but instead comprises all variations, modifications, substitutions and combinations which the person skilled in the art may infer from the present documents, especially in the context of the claims and the general remarks in the introduction of this specification, as well as the description of the embodiments, and combine with his expert knowledge, as well as the prior art. In particular, all individual features and configuration possibilities of the invention and its embodiments can be combined. 

1. Propulsion drive (P) with an underwater housing (6; 11) arranged on the bottom of a ship's hull, in which at least one propeller (5; 18) is mounted, being driven by a drive train of drive motor mechanisms (12) lying at least partly inside the underwater housing (6; 11), characterized in that a planet gear (4; 14, 15) is connected in series in the interior of the underwater housing (6; 11) to the at least one propeller (5; 18), and the planet gear (4; 14, 15) contains a sun wheel, which is configured as a part of a propeller shaft (2, 17), which is mounted in the underwater housing (6; 11) and on which the at least one propeller (5; 18) is seated outside of the underwater housing (6; 11).
 2. Propulsion drive per claim 1, characterized in that the sun gear is an integral component of the propeller shaft (2; 17).
 3. Propulsion drive per claim 1, characterized in that the bearing of the sun wheel with propeller shaft (2; 17) in the underwater housing (6; 11) also absorbs the forces and torques of the propeller (5; 18) and directs them into the underwater housing (6; 11).
 4. Propulsion drive per claim 1, characterized in that the sun wheel is divided and the forces and torques of the propeller (5; 18) and the planet gear (4; 14, 15) are transmitted via the connection, especially a screw connection.
 5. Propulsion drive per claim 1, characterized in that the sun wheel with propeller shaft (2; 17) is in a floating bearing or a double-sided bearing.
 6. Propulsion drive per claim 1, characterized in that another gear assembly is arranged between the planet gear (4; 14, 15) and the drive motor mechanisms.
 7. Propulsion drive per claim 6, characterized in that the other gear assembly is a ring gear/bevel gear transmission.
 8. Propulsion drive per claim 7, characterized in that the ring gear/bevel gear transmission contains a bevel gear set (1).
 9. Propulsion drive per claim 6, characterized in that a hydrodynamic coupling or a hydrodynamic converter is arranged between the planet gear (4; 14, 15) and the other gear assembly, especially the bevel gear stage.
 10. Propulsion drive per claim 1, characterized in that the planet gear (4; 14, 15) contains three to six planet wheels (3; 15).
 11. Propulsion drive per claim 1, characterized in that two propellers are present, one of which is arranged and designed as a pusher propeller and one as the tractor propeller of the propulsion drive (P).
 12. Propulsion drive per claim 1, characterized in that a propeller is arranged and designed as a tractor propeller of the propulsion drive (P) is present, and the propeller wash passes across the underwater housing (6; 11).
 13. Propulsion drive per claim 1, characterized in that a propeller (5; 18) is present, which is arranged and designed as a pusher propeller of the propulsion drive (P) and which takes in fluid via the underwater housing (6; 11).
 14. Propulsion drive per claim 1, characterized in that the drive motor mechanisms (12) contain a motor arranged in the underwater housing, which is connected in series to the planet gear (4; 14, 15).
 15. Propulsion drive per claim 14, characterized in that the motor (12) is an electric motor.
 16. Propulsion drive per claim 15, characterized in that the electric motor (12) is a permasyn, induction, synchronous, HTS or HY electric motor. 